Fog and Haze Along the Himalaya

View Image Comparison View Both Images Since mid-October, smoke from crop fires in Punjab and Haryana has blown across northern India and Pakistan. With the arrival of cooler weather in November, the smoke mixed with fog and industrial pollution to form a particularly thick haze. On November 7, 2017, the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite captured this natural-color image of haze blanketing the region. The second image, a data map based on observations from the same sensor, depicts aerosol optical depth , a measure of how airborne particles change the way the atmosphere reflects and absorbs visible and infrared light. Clear skies are white; skies thick with haze are red-brown. In New Delhi, where levels of pollution rose several times above the limit considered safe, authorities declared a public health emergency, closed elementa...